In this model, bacteria and fungi grow on dead leaves, dead insects and animal droppings. What is their main effect on the web?
They add new energy to the web by capturing sunlight
They raise the energy available to the top predators directly
They turn heat back into stored chemical energy
They break down dead material and return nutrients to the environment✓الإجابة الصحيحة
الشرح
Decomposers break dead organic matter into simpler substances and release nutrients that plants can take up again. The choice about turning heat back into stored energy fails, because energy lost as heat never returns to the web.